If your computer is Windows 2000 or Windows XP, double click My Computer, double click Control Panel, and double click "Phone and Modem Options." In the white box, highlight the location, and click on the Edit button. Place a checkmark in the "To disable call waiting, dial" box. Type *70, in the box. Click Apply, and click OK. Then, click Apply, and click OK again to close out the next window. This should disable call waiting when you are on the internet.